season, how does that change the way dealing with this job? is it a lot more stuff in there? . >> what we do, charles, we do this quarterly. every four months we go around and clean all the heat exchangers so we don't have a large build up. . >> go around? . >> yeah. (sound of hammering). >> what i'm trying to do, charles, is always pull it out on the low stroke. >> right. so you are not, like, flying out. now talk about clean up.